1. Field of the Invention
The present invention relates generally to a driver for screws, and more particularly to a screw driving member capable of fast engaging screws with a polygonal head for turning.
2. Description of the Related Art
It is very common to turn a screw by a power tool. Usually the power tool is able to be replaced with various drivers and sockets to drive different kinds or sizes of screws. To improve efficiency, some power tools are equipped with a screw loading apparatus to load screws in sequence into the power tool that users may operate the power tool without having to repeatedly reload the screws.
When a screw is turned by a driver, the driver should be aligned with a center of the screw and engaged with a slot on a head thereof. Walls of the slot may be damaged when the driver is over turning the screw. Therefore, the force of the power tool on the screw should be limited.
When a screw is turned by a socket, such screw has a polygonal head (usually it is hexagonal) to be engaged with the socket. With this polygonal head there is a greater contact area between the head of the screw and the socket so that the power tool may provide greater power to turn the nut before it is damaged. The only drawback is that the socket needs to aim at a specific angle for engagement with the screw. Before the screw is engaged with a turning socket, the process of aiming for a right angle may already damage the corners of the head.
In conclusion, both driver and the socket have their advantages and disadvantages. The advantage of the driver is fast engagement, but its output power is poor; the advantage of the socket is with greater output power, however, inconvenient engagement and screw head's corner damage is its weak part.